Compounds with direct immunotoxic properties, including metals, mycotoxins, agricultural pesticides and industrial chemicals, form potential human health risks due to exposure through food, drinking water, and the environment. Insights into the mechanisms of action are currently lacking for the majority of these direct immunotoxicants. Therefore, the present work aimed to gain insights into the molecular mechanisms underlying direct immunotoxicity. To this end, we assessed in vitro the effects of 31 test compounds on the transcriptome of the human Jurkat T cell line. These compounds included direct immunotoxicants, immunosuppressive drugs with different mode of actions, and non-immunotoxic control chemicals. Pathway analysis of the microarray data allowed us to identify canonical pathways and Gene Ontology processes that were transcriptionally regulated in common by immunotoxicants (i) with structural similarities, such as the tributyltins TBTC and TBTO that activated the retinoic acid / X receptor (RAR / RXR) signaling pathway, and (ii) without structural similarities, such as As2O3, DBTC, diazinon, MeHg, ochratoxin A, S9 treated ochratoxin A, S9 treated cyclophosphamide, and S9 treated benzo[a]pyrene, that activated unfolded protein response, and FTY720, lindane, and propanil, that activated the cholesterol biosynthesis pathway. In addition, processes uniquely affected by individual immunotoxicants were identified, such as the induction of Notch receptor signaling and the down regulation of acute phase response genes by ochratoxin A. These findings were validated by quantitative Real-Time PCR (Q-RT-PCR) analysis of genes involved in these processes. Our study indicated that diverse modes of action are involved in direct immunotoxicity and that a set of pathways or genes, rather than one single gene can be used to screen compounds for direct immunotoxicity.
Toxicogenomics-based identification of mechanisms for direct immunotoxicity.
Specimen part, Cell line
View SamplesThe transcriptional regulator EVI1 has an essential role in early hematopoiesis and development. However, aberrantly high expression of EVI1 has potent oncogenic properties and confers poor prognosis and chemo-resistance in leukemia and solid tumors. To investigate to what extent EVI1 function might be regulated by posttranslational modifications, we carried out mass spectrometry- and antibody-based analyses and uncovered an ATM-mediated double phosphorylation of EVI1 at the carboxy-terminal S858/S860 SQS motif. In the presence of genotoxic stress, EVI1-WT (SQS), but not site mutated EVI1-AQA was able to maintain transcriptional patterns and transformation potency, while under standard conditions carboxy-terminal mutation had no effect. Maintenance of hematopoietic progenitor cell clonogenic potential was profoundly impaired with EVI1-AQA compared with EVI1-WT, in particular in the presence of genotoxic stress. Exploring mechanistic events underlying these observations, we showed that after genotoxic stress EVI1-WT, but not EVI1-AQA increased its level of association with its functionally essential interaction partner CtBP1, implying a role for ATM in regulating EVI1 protein interactions via phosphorylation. This aspect of EVI1 regulation is therapeutically relevant, as chemotherapy-induced genotoxicity might detrimentally sustain EVI1 function via stress response mediated phosphorylation, and ATM-inhibition might be of specific targeted benefit in EVI1-overexpressing malignancies. Overall design: Poly-A RNA sequencing (RNAseq) analysis of EVI1-mediated modulation of gene expression RNA was extracted from HEK293 cells, which were subjected to transient transfection using half confluent cultures with pCMV-flag, pCMV-EVI1-WT-flag or pCMV-EVI1-AQA-flag, exposed to 150 µM H2O2 or left untreated for 8 h.
EVI1 carboxy-terminal phosphorylation is ATM-mediated and sustains transcriptional modulation and self-renewal via enhanced CtBP1 association.
Cell line, Treatment, Subject
View SamplesMouse aorta smooth muscle cells (SMCs) express TNF receptor superfamily member 1A (TNFR1) and lymphotoxin receptor (LTR). Circumstantial evidence has linked the SMC LTR to tertiary lymphoid organogenesis in diseased aortae of hyperlipidemic mice. Here, we explored potential roles of TNFR1 and LTR activation in cultured SMCs. TNFR1 signaling by TNF activated the classical RelA NF-B pathway, whereas LTR signaling by agonistic anti LTR antibody activated both the classical RelA and alternative RelB NF-B pathways. Addition of both agonists synergized to enhance p100 inhibitor processing to the p52 subunit of NF-B and promoted its nuclear translocation suggesting RelA-RelB cross-talk in transcription regulation. Correspondingly, microarrays showed that simultaneous TNFR1 and LTR activation when compared to activation of single receptors was followed by markedly elevated levels of mRNAs encoding leukocyte homeostatic chemokines CCL2, CCL5, CXCL1, and CX3CL1. Furthermore, SMCs acquired prototypical features of mesenchymal cells known as lymphoid tissue organizers (LTOs), which control tertiary lymphoid organogenesis in autoimmune diseases, through hyperinduction of CCL7, CCL9, CXCL13, CCL19, CXCL16, VCAM-1, and ICAM-1. Experiments with ltbr-/- SMCs suggested that the LTR-RelB activation component of NF-B signaling was obligatory to generate the LTO phenotype. TNFR1-LTR crosstalk also resulted in augmented synthesis and prolonged secretion of lymphorganogenic chemokine proteins into the culture medium. Thus, combined TNFR1-LTR signaling triggers SMC transdifferentiation into a phenotype that strikingly resembles LTOs. LTO-like SMCs may adopt a thus far unrecognized role in diseased arteries, i.e. to coordinate tertiary lymphoid organogenesis in atherosclerosis, aortic aneurysm, and transplant vasculopathy.
Mouse aorta smooth muscle cells differentiate into lymphoid tissue organizer-like cells on combined tumor necrosis factor receptor-1/lymphotoxin beta-receptor NF-kappaB signaling.
No sample metadata fields
View SamplesCultured mouse aorta endothelial cells (from 8-12 weeks old C57BL/6J mice, passage 2-3) were exposed to phosphate buffered saline (control) or a combination of TNFalpha plus agonistic alpha-LTR antibody for 24 hours as described in Ltzer et al. 2009. Arterioscler. Thromb. Vasc. Biol., in press. Total RNA was extracted and microarrays were prepared.
Mouse aorta smooth muscle cells differentiate into lymphoid tissue organizer-like cells on combined tumor necrosis factor receptor-1/lymphotoxin beta-receptor NF-kappaB signaling.
Specimen part
View SamplesMultipotent progenitor cells (MPs) have been observed in human kidneys and particularly in Bowman's capsule and proximal tubules. The kidney owns the ability to repair local damage and renal MPs may play a role in the regenerative processes. Microarray technology was applied to identify differentially expressed genes among resident MPs isolated from glomeruli and tubules of normal renal tissue, renal proximal tubular epithelial cells (RPTECs) and mesenchymal stem cells (MSCs).
TLR2 plays a role in the activation of human resident renal stem/progenitor cells.
Subject
View SamplesThe hallmark of IgA nephropathy (IgAN) is gross hematuria (GH) coinciding with or immediately following an upper respiratory or gastrointestinal tract infection and can represent the disease triggering event. Therefore, a whole genomic screening of IgAN patients during the GH was done to clarify the link between mucosal encountered antigens and the occurrence of glomerular hematuria. The modulated genes during GH show a clear involvement of the interferon signalling, antigen presenting pathway, and the immuno-proteasome. The gene characterizing cytotoxic effector lymphocytes (CX3CR1) implicated in vascular endothelial damage, was found up-regulated at both mRNA and protein level. In vitro antigenic stimulation of PBMCs on an independent set of IgAN patients and healthy blood donors (HBS) demonstrated that patients upregulate specifically CX3CR1 in an enhanced and dose dependant manner, while an expected down-regulation occurred in HBD. This enhanced activation occurred in both patients characterized by recurrent GH and by permanent microscopic hematuria (MH). We then analyzed glomerular fractalkine (FKN) expression, since this ligand is involved in the vascular gateway for CX3CR1+ cells towards the inflamed tissues. A significantly higher FKN expression on the capillary vessels and podocytes was found in recurrent GH patients compared to permanent MH, suggesting a predisposition for cytotoxic cell extravasation in recurrent GH patients.
Activated innate immunity and the involvement of CX3CR1-fractalkine in promoting hematuria in patients with IgA nephropathy.
Sex, Specimen part, Disease, Disease stage, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Temporal- and strain-specific host microRNA molecular signatures associated with swine-origin H1N1 and avian-origin H7N7 influenza A virus infection.
Cell line
View SamplesMicroRNAs (miRNAs) repress the expression levels of genes by binding to mRNA transcripts, acting as master regulators of cellular processes. Differential expression of miRNAs has been linked to viral-associated diseases involving members of the hepacivirus, herpesvirus, and retrovirus families. In contrast, limited biological and molecular information has been reported on the potential role of cellular miRNAs in the lifecycle of influenza A viruses (infA). In this study, we hypothesize that elucidating the miRNA expression signatures induced by low-pathogenic swine-origin influenza A virus (S-OIV) pandemic H1N1 (2009) and highly pathogenic avian-origin (A-OIV) H7N7 (2003) infections could reveal temporal and strain-specific miRNA fingerprints during the viral lifecycle, shedding important insights into the potential role of cellular miRNAs in host-infA interactions. Using a microfluidic microarray platform, we profiled cellular miRNA expression in human A549 cells infected with S- and A-OIVs at multiple time-points during the viral lifecycle, including global gene expression profiling during S-OIV infection. Using target prediction and pathway enrichment analyses, we identified the key cellular pathways associated with the differentially expressed miRNAs and predicted mRNA targets during infA infection, including immune system, cell proliferation, apoptosis, cell cycle, and DNA replication and repair. By identifying the specific and dynamic molecular phenotypic changes (microRNAome) triggered by S- and A-OIV infection in human cells, we provide experimental evidence demonstrating a series of temporal- and strain-specific host molecular responses involving different combinatorial contributions of multiple cellular miRNAs. Our results also identify novel potential exosomal miRNA biomarkers associated with pandemic S-OIV and deadly A-OIV-host infection.
Temporal- and strain-specific host microRNA molecular signatures associated with swine-origin H1N1 and avian-origin H7N7 influenza A virus infection.
Cell line
View SamplesWe previously observed that formation of aorta and innominate artery atherosclerotic lesions in the intima of hyperlipidemic apoE-deficient mice but not wild-type mice was accompanied by a marked age-dependent adventitial T cell infiltration. As the mice aged, adventitial T cells formed T/T cell-, T/B cell-, and T/B/dendritic cell aggregates adjacent to atherosclerotic lesions. Some of the adventitial infiltrates formed large clusters of various immune cells including T cells, B cells (centrocytes, follicular mantle cells), dendritic cells, follicular dendritic cells, and plasma cells with preferential formation in the suprarenal portion of the abdominal aorta. These data demonstrated that the immune lineage cell composition of atherosclerotic lesions and adventitia were distinct: The macrophage-foam cell-, T cell-, and SMC-dominated cell composition of atherosclerosis lesions versus the presence of immune cells capable of carrying out antigen-dependent T cell-driven humoral immune responses in the adventitia also indicated that immune reactions carried out in lesions or the adventitia are fundamentaly different. To distinguish between immunity-regulating genes in atherosclerosis lesions versus the adventitia, a combination of microarray profiling and laser capture microdissection was used. Stringent filters revealed 1163 differentially up-regulated probesets in apoE-/- mouse aortae at 78 weeks (w) versus 6 w. A fuzzy c-means cluster algorythm identified 2 clusters that significantly differed in their slope angles between time points: An apparent atherosclerosis cluster consisted of 771 probesets and an apparent adventitia cluster consisted of 392 probesets. Up-regulated genes at 32 w mirrored the influx of monocyte/macrophages into intima lesions whereas genes up-regulated between 32-78 w mirrored adventitial inflammation. To segregate both clusters into separate gene ontology (GO) molecular function groups, we determined statistically significant up-regulation (unpaired Student t-test; p < 0.05) between 6-32 w for the atherosclerosis cluster and between 32-78 w for the adventitia cluster. Among others, GO molecular function terms cytokine activity, cytokine binding, and immunoglobulin binding in the atherosclerosis cluster and cytokine activity, chemokine receptor activity, and antigen binding in the ATLO cluster suggested candidate genes in relation to inflammation triggered by macrophages or adventitia infiltration, respectively. Among other prototype atherosclerosis genes such as Itgax (complement receptor 4), Cd68, Lysz (lysozyme), Vcam1, and Icam1, the atherosclerosis cluster showed markedly overrepresented prototype macrophage/foam cell genes regulating inflammation in cytokine activity (GO: 0005125): Spp1 (osteopontin) and Il6; in cytokine binding (GO: 0019955) Cd74, Il10rb, Ccr2, and Ccr5; and in immunoglobulin binding (GO: 00119865) the proinflammatory galactose-binding lectin Lgals3, as well as genes in scavenger receptor activity and lipid transporter activity. By contrast, the adventitia cluster showed overrepresented genes regulating B cell recruitment, B cell maturation, germinal center formation, and autoimmunity in cytokine activity including Cxcl13, Ccl21, and Ltb, in CXC chemokine receptor activity the secondary lymphoid organ counterreceptor of CXCL13 Blr1 (also known as Cxcr5), Cxcr3, and Cxcr6; and in antigen binding several histocompatibility-2 loci and various markedly expressed immunoglobulin genes. As embryonic lymph node development and tertiary lymphoid organ neogenesis share common features signal intensities of genes specifying the GO molecular function term lymph node development (GO: 0048535) were examined in arrays prepared from wild-type and apoE-/- aortae. These results showed that Id2, Nfkb1, and Ltbr were constitutively expressed at significant levels in aortae of both mouse genotypes whereas other genes including Lta, Ltb, Glycam1, and the two lymphorganogenic genes Cxcl13 and Ccl21 were induced at 78 w in apoE-deficient aortae only. Thus, genes expressed by macrophage-foam cells and genes regulating ATLO neogenesis, embryonic lymph node development, or B cell maturation were constitutively expressed in the arterial wall in both genotypes or emerged in a stepwise fashion at 32 w and 78 w. To verify microarray signal intensity data, separate aortae extracts were examined by quantitative RT-PCR (QRT-PCR) analyses of wild-type and apoE-deficient mice at 32 and 78 w. These data showed that array signal values accurately reflected gene transcripts. Cell lineage analyses of the adventitial infiltrate and kinetic aorta microarray- and QRT-PCR analyses thus provided circumstantial evidence that immune responses in atherosclerosis intima lesions and the adventitia were distinct. To examine this possibility further, we selected areas of the abdominal aorta burdened with advanced lesions and separated lesions and corresponding adventitial infiltrates of 78 w old apoE-deficient mice by laser dissection microscopy. In addition, adventitiae of aorta segments that were not associated with adjacent lesions and adventitiae of wild-type mice were prepared. Consistent with the lack of a major adventitial leukocyte infiltration, wild-type adventitiae showed gene expression levels that were similar to lesion-free adventitiae of apoE-deficient mice indicating that atherosclerotic lesions directly affected adventitial inflammation in a segmental fashion. Stringent filter criteria identified genes that were differentially expressed in adventitiae and atherosclerotic lesions. Statistical analyses of overrepresented genes in GO molecular function or biological process groups were particularly instructive in cytokine activity, cytokine binding, antigen processing and presentation as well as in lymph node development. Thus, adventitiae in aorta segments with associated atherosclerotic lesions in cytokine activity showed overrepresentation of genes known to be associated with tertiary lymphoid organ formation including Cxcl13, Ccl21, and Ltb, whereas atherosclerotic lesions showed overrepresentation of prototype atherosclerosis-associated genes Ssp1 (osteopontin), Bmp4 (bone morphogenic protein 4), and Cxc3cl1 (fractalkine); in cytokine binding adventitiae showed overrepresentation of receptors implicated in B cell immunity and autoimmunity including Brl1 (counterreceptor for CXCL13), Ccr7, Tnfrsf4, and Cxcr3 whereas lesions showed overrepresentation of inflammatory mediator receptors including Tnfrs1b, Tgfbr1, and Il7r; moreover, in antigen processing and presentation, adventitiae showed overrepresentation of several histocompatibility loci; additional adventitial gene expression overrepresentations were observed in lymph node development (Fas, SpiB, Ltb, Flt3) whereas lesions showed expression of prototype macrophage genes including Tlr4, Tgfb1, and Tgfb2. These data provide comprehensive topographical transcriptome information in adventitial tissue adjacent to atherosclerotic lesions versus lesions and are expected to form the basis for future cell lineage expression analyses using single cell detection methodology including ISH.
Lymphotoxin beta receptor signaling promotes tertiary lymphoid organogenesis in the aorta adventitia of aged ApoE-/- mice.
Sex, Age, Specimen part
View SamplesThe inner ear in mammals is derived from a simple ectodermal thickening called the otic placode. Through a series of complex morphological changes, the placode forms the mature inner ear comprising of the auditory organ (cochlea) and the vestibular/balance organs (utricle, saccule, and three semi-circular canals). The vast majority of genes known to be involved during inner ear development have been found through mutational screens or by chance.
Toward a systems biology of mouse inner ear organogenesis: gene expression pathways, patterns and network analysis.
Specimen part
View Samples